Cardiovascular Flashcards
Ectopia cordia
Heart develops outside the body cavity, due to incomplete body compartments
Amorphus globosus
Acardiac monster attached to the placenta. Spherical, covered in hair
Patent ductus arteriosus
Foetal remnant which connects the aorta and pulmonary artery.
Blood shunts from aorta to pulmonary artery therefore leading to pulmonary hypertension.
Usually degenerates to the Ligamentum arteriosum
Sequelae to PDA
Right ventricular hypertension due to pulmonary hypertension
Patent foramen ovale
Hole which allows blood from the right atrium to by-pass the lungs during gestation
True septal defect
A hole (fault) in the septum between heart chambers.
Can be interatrial or interventricular.
With ventricular shunts are from left to right and lead to equal pressures in the chambers:
- Volume overload and eccentric hypertrophy in the right atrium
- Pressure overload and concentric hypertrophy in the left atrium
Pulmonary stenosis
Valvular lesions which are associated with muscle/fibrous tissue deposition:
- Subvalvular - beneath the valve
- Valvular - valve itself
Leads to pressure overload and concentric hypertrophy of the right ventricle. Also jet lesions in the pulmonary artery.
Subaortic stenosis
Below the aortic valve a zone of circumferencial fibrosis.
Made up of proliferating mesenchyme, mucin and metaplastic cartilage.
Leads to pressure overload and concentric hypertrophy of the left ventricle. Also myocardial necrosis and fibrosis may be observed.
Tetralogy of fallot
- Ventricular septal defect
- Pulmonic stenosis
- Dextroposition of the aorta - aorta straddles right and left ventricles
- Secondary hypertrophy of the rght ventricle
Baby blue syndrome - cyanosis
Valvular haematoma
Haemocyst/ lymphocyst - generally regress
Persistent right aortic arch
Ligamentum arteriosum forms a ring around the oesophagus and trachea.
Leads to cranial megaoesophagus - regurgitation
Peritoneopericaridial diaphragmatic hernia
Displacement of the intestine into the pericardium.
Hydropericardium
Transudate or exudate (+ fibrin - associated with mulberry heart disease)
Associated with generalised oedema and therefore cardiac tamponade and compression
Haemorrhagic pericardial effusion
Small deposits of blood
GSD
Haemopericardium
Large amounts of blood within the pericardium.
Causes:
Atrial rupture due to haemangiosarc
Aortic rupture in horses
Iatrogenic
Pneumopericardium
Due to pulmonary rupture/ oesophageal rupture
Chylopericardium
Exudate formed due to rupture of the thoracic duct
Describe this value.
Epicardial fat has become yellow and gelatinous. Due to fat metabolism (starvation).
Histologically appears oedematous and atrophic
Describe this lesion
What are the potential outcomes of the condition
Subacute diffuse severe fibrinous pericarditis
(traumatic, haematogenous, local spread of infection)
Histo - fibrin layer with n# over pericardium
Outcomes - death through septicaemia or chronicity (proliferating fibrosis) with compensatory hypertrophy &heart failure
Cause of fibrinous pericarditis in:
- Cat
- Cattle
- Pig
- Horse
- Bird
- FIP
- Pasturella, C. chauvoei, Chlamidophila, collisepticaemia
- Haemophilus parasuis, streps, pasturella, Salmonella, Mycoplasma hyopneumoniae
- Streps
- Chlamydia psittaci
Polyserositis
Pig?
Inflammation of several serous membranes - eg pleural, pericardium, peritoneum
Glasser’s disease - Haemophilus parasuis
Pericardial gout
Causes..
Accumulation of uric acids - found in reptiles/ birds
Causes:
- Enzyme deficiency
- Dietary
- Increased catabolism - disease/ tumours
- Renal disease
- Dehydration
Grossly see white urate crystals on the pericardial surface
Endocardial mineralisation
Excess vitamin D intake or calcinogenic plant intoxication, Hyperparathroidism, renal failure, Johne’s
Basically due to hypercalcaemia
Endocardial fibrosis
Chronic dilation, healing ulcerative endocarditis, jet lesions.
Appears as firm white plaques in endocardium and intima of large vessels
Myxomatous degeneration
Degenerative disease which accumulates mucin
Valvular endocardiosis
Degeneration of valvular collagen - degenerative change in older dogs
Left ventricular endocardial fibroelastosis
Depositation of fibroelastic tissue on endocardium (due to deposition and poor lymph drainage in the myocardium)
Can result in decreased CO, CHF and left-bundle block
What bacterial species are associated with endocarditis?
Ecoli/ streps in dogs
A. pyogenes in cattle
Streps in pigs
Describe this lesion
Multifocal to coelescing rough, irregular nodules. Endocardium remaining is reddened.
Acute mf-c severe fibrinous endocarditis
Valvular injury leads to bacterial adhesion and proliferation.
Chronically fibrosis occurs
Sequelae to valvular endocarditis
Valvular dysfunction - regurgitation, systemic/ pulmonic hypertension
Atrial dilation and thromboembolism creation
Bacteriaemia
Aneurysm
Localised dilation of a thinning and weakened portion of a vessel.
Usually affects arteries
- Copper deficiency in pigs
- Spirocerca lupi
- Disecting in birds
What can lead to vessel rupture in animals?
Aneurysm
Traumatic - horse falls over, cow during parturition
Mycosis - internal carotid
Arterial hypertrophy
Sustained high pressure or volume within the artery - compensatory hypertrophy of smooth muscle
- Parasitic - toxocara, heartworm, lung worm
- Brisket disease - sustained vasoconstriction in response to generalised hypoxia
- Cardiovascular shunts
Medial calcification
Causes?
Endocardial mineralisation and fibrosis
Causes:
- Vit D toxicosis
- Renal insufficiency
- Johne’s
- Plant toxicosis
Basophilic material within the tunica media of vessels
(Intima may be a normal finding)
Fibrinoid necrosis - endothelial damage and inflammation spills into surrounding tissue - fibrin deposits within interstitial tissue
Caused by selenium/ vit E deficiency in pigs/ oedema disease, uraemia
Thrombosis
Intravascular coagulation
There are three factors involved:
- Endothelial injury - eg parasitic
- Hypercoagulability - congenital, dehydrated
- Abnormal blood flow - stasis, turbulence, emboli
Describe this lesion
A solid mass within the aortic bifurcation of this cat (aka a saddle thrombus). Blocks blood flow to and from the caudal tissues
Thrombosis due to Dirofilaria immitis would most likely end up where?
Pulmonary arteries/ right ventricle
Thrombosis due to Strongyloids will most likely be found where?
Mesenteric artery of the gut
Disseminated intravascular coagulation
Concurrent clotting and coagulation within the blood.
Extensive clotting depletes resources leading to widespread haemorrhage. Also activation of the coagulation scale.
Embolism
What are the four different types of emboli?
Occlusion of arteries by foreign material
- Septic - vegetative endocarditis
- Parasitic - fragments of dead parasites (due to anthelmintic treatment)
- Fat - bone fracture
- Fibrocartilagenous - spinal arteries due to fragmented discs
- Thromboembolism - pulmonary arteries (imha, ple)
Causes of arteritis
Haematogenous spread of infection
Local spread of infection
Immune mediated (t3 hypersensitivity)
Parasitic
Name one cause of vasculitis from each of these categories.
- Viral
- Bacteria
- Fungi
- Parasite
- Immune-mediated
- EVA, BVDV, BTV
- Salmonella, erysipelas
- Aspergillus
- Strogyloides
- SLE
Phlebitis
Causes
Vein inflammation
- Systemic infection
- Local infection
- IV injection
Omphalophlebitis
Navel ill
Inflammation of the umbilical vein in a neonate due to infection of the site post-partum
How can hepatic abscessation lead to thrombosis in the lung?
Local spread of infection from the hepatic vein to the vena cava, caval thrombosis travels to the heart and then the pulmonary system
Haemangiopericytoma
Characterised by whorls of fusiform cells surrounding vessels
How can mitral valve disease lead to atrial rupture?
Valvular incompetence leads to voume overload of the atrium during systole
This leads to thinning of the atrial walls and eventually rupture of the structure
Eccentric ventricular hypertrophy
Due to volume overload the ventricle dilates with an increase in wall thickness
Caused eg by valvular insufficiency/ septal defect
Concentric hypertrophy
Increase wall thickness and decreased chamber size caused by pressure overload.
Caused by stenosis or systemic/ pulmonary hypertension
Ventricular dilation without hypertrophy is due to…
Inability of the muscle to undergo hypertrophy - disease, nutrition
Stretching of cells allows increased contractile force and stroke volume
Describe this lesion
Severe concentric hypertrophy of the ventricles with subsequent dilation of the left atria
Histologically can see degenerate myocytes, interweaving fibres and fibrosis
Describe this lesion
Dilated ventricle, endocardium is diffusely white, increased heart weight
Histologically there may be NO changes, or similar to that of hypertrophic
Clinical signs would include effusions, dyspnoea (compressing airway), subcut oedema
Restrictive cardiomyopathy
Walls are rigid - reduced filling
This genetic condition leads to fibrosis of cardio-myocytes
X-linked muscular dystrophy
Muscular atrophy, interstitial fat deposits and fibrosis
Myocardial necrosis
Pale yellow areas within the myocardium, dry, gritty (mineralisation)
Describe the progression of histological features of myocardial necrosis.
- Dilated, hypereosinophilic (necrotic) myocytes
- Infiltrated by inflammatory cells (n# and macrophages) - acute
- Infiltrated by fibroblasts - collagen and vascularisation
Describe this lesion
Mottled colour of myocardium
Areas of haemorrhage
Fibrinoid necrosis
Acute diffuse severe haemorrhagic and necrotisin myocarditis
Caused by vitaminE/ selenium deficit - mulberry heart disease (high fat diets)
Myocardial degeneration in equine
petechial haemorrhage pericoronal
Monensin poisoning
Lymphocytic myocarditis
Parvovirus (likes rapidly dividing cells) cardiacmyocytes in puppies
Purulent myocarditis
Veg endocarditis
Local bacterial spread
Black leg
Leads to myocarditis - Clostridium chauvei
Chemodectoma
At aortic base - tumour of the chemoreceptor cells
